Aneurysmal Subdural Hematoma: A Systematic Review.

ABSTRACT

BACKGROUND: Aneurysmal subdural hematoma (aSDH) is a rare complication of aneurysm rupture, affecting between 0.5 and 7.9% of patients with aneurysmal subarachnoid hemorrhage (aSAH). The clinical presentation, course, and outcomes of these patients are largely unknown. OBJECTIVE: This study aims to systematically review the literature to evaluate the demographics, clinical presentation, aneurysm location, treatment options, and outcomes of patients with aSDH with and without aSAH. METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we conducted a systematic review of three databases (PubMed, EMBASE, and Google Scholar). From identified reports, we extracted data on patients' demographics, clinical presentation, imaging findings, surgical interventions, and clinical outcomes. We compared clinical outcomes, need for surgical treatment, and aneurysm location between patients with aSDH with and without concurrent aSAH using χ2 and Fisher's exact tests. We used simple and multivariable logistic regression models to further examine the association between the presence of aSAH and surgical treatment with clinical outcomes. RESULTS: We identified 112 articles with a total of 270 patients (70% women, mean age 52.8 [± 15.5] years). The most common aneurysm locations were the middle cerebral artery, followed by the posterior communicating artery, and the internal carotid artery. Patients with isolated aSDH fully recovered more frequently than those with concomitant aSAH (38% vs. 6%). The presence of aSAH increased the odds of unfavorable outcome (odds ratio [OR] 2.68, 95% confidence interval [CI] 1.34-5.37). Surgical treatment was inversely associated with unfavorable outcome in the univariable (OR 0.48, 95% CI 0.28-0.84) but not in the multivariable analysis (OR 0.76, 95% CI 0.35-1.66). CONCLUSION: aSDH occurs infrequently. Simultaneous presence of both aSDH and aSAH from an aneurysmal source is associated with poor outcomes. Surgical treatment is associated with lower rates of unfavorable outcomes including death and severe disability.